Officials Describe Loss of Nuclear Secrets at Los Alamos

By JAMES RISEN

Published: December 12, 1999

WASHINGTON, Dec. 11—
When a former scientist at the Los Alamos National Laboratory was indicted on Friday on charges that he had improperly removed American nuclear secrets from the lab, the government outlined a possible compromise of classified information far greater than previously disclosed.

Although he was not charged with espionage, senior government officials now say that Wen Ho Lee, the former Los Alamos scientist arrested Friday and charged in the case, jeopardized virtually every nuclear warhead in the American arsenal through unauthorized computer transfers of many of the country's most sensitive nuclear secrets.

The officials also said much of the information Dr. Lee removed was missing because he had copied the data onto portable computer tapes, many of which the Federal Bureau of Investigation cannot find. The officials said they found the methodical and comprehensive way in which the data had been copied particularly alarming.

Although early accounts of the investigation described nuclear secrets being mishandled on a large scale, never before has the complex case been presented in such detail.

The key to the government's case, and what finally persuaded prosecutors to seek an indictment and arrest Dr. Lee, is the evidence developed by F.B.I. computer experts to show that Dr. Lee copied thousands of pages of nuclear-related documents onto 10 computer tapes in 1993, 1994 and 1997. Only three of those tapes have been recovered.

Officials said it was the discovery that the tapes were missing and the extraordinary breadth of the secret nuclear details on them, more than the initial discovery of Dr. Lee's unauthorized transfers of data, that prompted the government to treat the case so seriously.

A federal grand jury in Albuquerque issued a 59-count indictment against Dr. Lee, charging him with violations of the Atomic Energy Act and the Foreign Espionage Act. Some of the most serious offenses are punishable by life in prison.

It was previously known that Dr. Lee had, mainly in 1993 and 1994, transferred onto an unsecure computer system data used to design nuclear weapons, analyze nuclear test results and evaluate weapons materials and the safety characteristics of America's nuclear warheads. But in the indictment, the government said for the first time that Dr. Lee had transferred information in a more determined manner and for a far longer time than investigators initially believed.

The government charged that Dr. Lee had copied secret nuclear data onto a tape as recently as 1997. Officials initially believed that Dr. Lee's unauthorized computer activities had ended by 1995.

For example, the indictment says that in 1997, Dr. Lee copied onto a tape the ''complete source code for the current version'' of the government's most advanced design for an atomic bomb that acts as the trigger to explode a hydrogen bomb.

The government is also using evidence about the processes Dr. Lee used to transfer the material to argue that his actions were not accidental or intended to protect the information, as he has asserted. According to the indictment and government officials, as Dr. Lee moved the material from the classified network to an open system, he deleted markings identifying it as secret. After the material was in the open system, he copied it onto tapes on another employee's computer.

Dr. Lee is being held without bail pending a hearing on Monday. In a statement on Friday, Dr. Lee's lawyer, Mark Holscher of Los Angeles, said the charges against Dr. Lee were groundless.

The government is not saying Dr. Lee committed espionage by giving the classified information to another country or person.

In fact, while Dr. Lee's arrest was the culmination of an F.B.I. investigation into his computer activities that began in March, the espionage inquiry that first brought Dr. Lee to the government's attention is continuing at a much slower pace.

The government stumbled onto evidence of Dr. Lee's unauthorized computer transfers because he was under investigation in connection with an inquiry into evidence that China may have stolen secret data related to America's most advanced nuclear warhead, the W-88, which was designed at Los Alamos.

That investigation began in early 1995 by the Department of Energy, which owns the national weapons labs, and the F.B.I. The investigation started after American intelligence received sensitive information about a 1992 Chinese test of an advanced nuclear warhead that appeared to be modeled after an American weapon. Subsequently, the Central Intelligence Agency received a Chinese government document that included secret data about the W-88, indicating that the Chinese had obtained classified information from the American nuclear program.

By 1996, when the F.B.I. opened a formal criminal investigation, Dr. Lee had emerged as the prime suspect as the source of the leak.

But after the case became public in March, a national furor erupted over the way the government had handled the investigation, leading to a series of reviews of the actions of officials at the F.B.I. and the Energy and Justice Departments.

By September, the F.B.I. and the Justice Department had determined that the initial administrative inquiry by the Energy Department and the F.B.I. that began the investigation had been flawed and that investigators had prematurely focused on Dr. Lee.

Officials determined that the secret data about the W-88 included in the Chinese government document given to the C.I.A. in 1995 did not necessarily come from Los Alamos.

The Chinese document was dated 1988, and by that time the classified information on the W-88 included in the document might have been available at other laboratories or federal agencies, or even at defense contractors.

So the F.B.I. went back to square one on the W-88 case this fall, broadening its investigation in an effort to account for how the information about the warhead was disseminated through the government and its contractors. On Friday, a senior government official said that renewed inquiry is continuing on a separate track from the criminal case pending against Dr. Lee. He said Dr. Lee's indictment ''does not answer the original referral from the Department of Energy on the W-88.''

The official added that the Chinese intelligence service tended to rely on many sources. The Lee case ''could be one source, or it may have nothing to do with it,'' he said.